In California, Flawed Air Rules Threaten Farmworkers as Wildfires Pump More Smoke Onto Fields

Air pollution levels considered “safe” for farmworkers provide inadequate protection from health risks and injuries, a new study from University of California Davis finds.

OXNARD, Calif.—The January wildfires were still raging to the east in Pacific Palisades, torching thousands of homes and painting the Southern California sky a smudgy orange, but Adriana, a farmworker whose name has been changed to protect her identity, recalled trying to get to a strawberry field amid the chaotic response to the fires. 

It didn’t matter that the single mother of two was coughing up blood from breathing the smoke; she needed the money to pay rent. 

“Out of nowhere, I get a cough,” she said in Spanish. “It has been triggered by anything. By the cold, by the smoke. And I have been coughing so hard that blood has started coming out of my throat.”

Adriana was ultimately turned away that morning by firefighters blocking the highway—another day’s pay lost.

Adriana is among the hundreds of thousands of farmworkers in California, many of whom have migrated from Mexico and countries farther south in hopes of making a better life. But the work comes with an extremely high risk of accidents and illness. Adriana has suffered serious falls multiple times, and can feel her lungs weakening year by year—especially during wildfire season. Still, she shows up to work.

To protect workers like Adriana from the effect of wildfire smoke and harmful air pollution, California five years ago declared that whenever air pollution levels reach unhealthy levels, employers would have to take steps to protect their outdoor workers, potentially including handing out masks and adjusting work schedules. The U.S. government defines “unhealthy” as when levels of fine particles exceed 55 micrograms per cubic meter of air, an Air Quality Index (AQI) of 150.

But new research from scientists at the University California, Davis suggests the safety standard for small particles should be even stricter. The study by agricultural economists Timothy Beatty and Goeun Lee found that the thicker the smoke reaching the fields, the more likely traumatic injuries—including strains, tears, contusions and lacerations—will occur. Correlating injury claims with wildfire locations from 2007 to 2021, the authors concluded that “injuries occur even at levels considered safe” for wildfire smoke under California’s standard.

“Almost all air-quality regulations and wildfire-smoke protection policies in the United States rely on predefined thresholds for air-pollutant exposure, which assume that exposure at levels below these thresholds poses no important health risks,” the researchers wrote. “However, our research calls these thresholds into question.” 

They estimate at least 282 farmworkers suffered from wildfire smoke-related injuries in 2020 alone.  Researchers anticipate these numbers to rise as climate change intensifies the risk of extreme fire events by up to 57 percent at the end of the century. While the overall number of wildfires may not significantly increase, the likelihood of large-scale, high-intensity fires—known as megafires—is projected to grow substantially. A 2024 Nature study found that the frequency and magnitude of extreme wildfires have more than doubled globally since 2003, with the six of the world’s worst wildfire years occurring in the seven years immediately prior to the study’s release. 

These megafires tend to burn longer, spread farther and expose more people to hazardous smoke conditions.

Beatty and Lee used a statistical model that linked injury claims filed with California’s Division of Workers’ Compensation to wildfire smoke levels in each zip code. They focused on physical injuries like falls and cuts, which are more likely to be reported and reliably captured in the data.

“Non-traumatic injuries are more frequently denied than traumatic injuries because it’s pretty tricky to prove causal relationships in the workplace,” said Lee.

Lung and heart problems are harder to tie directly to work in the fields than falls and other traumatic injuries, Beatty and Lee said, and they often go unreported by farmworkers. While about one in 10 wildfire-season hospital visits in California are for respiratory problems, these make up less than 1 percent of injury claims from farmworkers, indicating that the real toll of wildfire smoke is likely much higher than what’s visible in the claims data alone. The researchers acknowledge that gap in the data, calling it the biggest limitation of the study.

“It is peeking through a keyhole,” Beatty said. “It’s not the sort of perfect data set.”

“What we wanted to look at was, ‘Do these sorts of wildfire smoke events, do they have sort of knock-on health effects (including injuries)?’” he added. “And the answer was ‘yes.’”

Adriana, for one, has only come to her supervisor for injuries she has sustained from falling as she handled strawberries, but has never thought of needing help for her lungs.

“I don’t think they can do anything about it,” said Adriana.

“These farmworkers are among the most vulnerable workers in the country,” said Daniel Jimenez, an outreach worker with United Farm Workers Foundation (UFWF). “Most of them are migrants. Many of them only speak Spanish and even Indigenous languages, so it’s hard for them to advocate for themselves.” 

Lee recommended that California lower its air pollution threshold to match those in states with stricter standards, and add more protections such as reducing work hours for farmworkers during wildfire days and then allowing them to work overtime on days with better air to make up for the lost pay. Washington has the lowest threshold for dangerous air in the United States. It triggers safety protocols at AQI levels as low as 72, roughly half the threshold that does that in California.

At AQI 72 in Washington, employers are required to inform their workers of the air quality; then only employees trained to work during bad air days can work outdoors. At AQI 101, the state mandates employers to distribute N95 masks and take other steps to lower workers’ exposure to smoke.

Lawmakers in Washington decided to “err on the side of public health protectiveness,” explained Eddie Kasner, an exposure scientist at the University of Washington whose work focuses on agricultural workers. “When you have lower thresholds, you start training and providing resources earlier, which is beneficial long-term.” 

To further protect farmworkers, Kasner recommended building cooling and clean-air tents to provide refuge from bad air and heat.

But for these protections to happen in California, its Division of Occupational Safety and Health would have to update its rules, a process that could take years.

“Wildfire smoke is certainly something we talk more about than we used to,” said Bryan Little, policy advocacy senior director of the California Farm Bureau. 

Compliance with the face mask rule is also challenging because workers would rather not wear them, Little said, as “[N95 masks] are not comfortable.” 

“Personal protective equipment compliance is generally difficult for all types. Nobody likes to wear respirators, goggles, and steel-toe shoes,” Little said.

And current state regulation makes it hard for farmers to implement flexible work times. 

California’s Assembly Bill 1066, enacted in 2016, gradually introduced overtime pay for farmworkers, granting them time-and-a-half pay after eight hours in a day or a 40-hour week, replacing the previous thresholds of 10 hours daily and 60 hours weekly. But this change, meant to ensure fair pay, has led employers to cut workers’ hours, reducing farmworkers’ flexibility to make up for missed work.

To address this, the Farm Bureau co-sponsored Senate Bill 628 to create tax credits for agricultural employers who pay overtime wages. As for paying farmworkers on days that wildfires suspend their work, Little said it’s a non-starter.

“Our margins are already so tight in agriculture that expecting agricultural employers to pay for that is a surefire way to guarantee we’re going to have even less agricultural employment in California,” he added.

Cal/OSHA is focused on fulfilling its role in being “proactive” at informing employers about the current rules, and directing farmers and farmworkers to the agency’s online resources, a spokesperson for the agency said.   

“Cal/OSHA generally responds to workplace hazards through direct complaints from workers or their representatives; reports of work-related serious illnesses, injuries, or fatalities; and proactive inspections. The agency has the authority to issue citations and fines to non-compliant employers,” the spokesperson said.

But the managers of farms that Adriana has worked on, she said, won’t even comply with the simple act of giving out masks, instead forcing farmworkers to rely on bandanas and scarves they wrap over their faces. 

She remembered one wildfire season when the flames were getting so close to the farm that her colleagues asked their boss if they could leave. “Only if it burns here,” she recalls the boss replying. 

Cover photo:  Adriana has been farming for over 20 years, migrating from Oaxaca, Mexico, to Oxnard, Calif. Adriana has suffered serious falls multiple times, and can feel her lungs weakening year by year. Credit: Rambo Talabong/Inside Climate News